New Build: GM 4.2L Atlas into '91 FJ80
- Thread starter TwoTonic
- Start date
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Is this going to be a retail part?
Efidiy, any idea what those pans will go for? TwoTonic, how about your t-case adapter? Personally since part of the swap goal would be to increase mileage a split case and set of lock-out hubs would be a nice way to go. Whichever route you go this is a very interesting swap, much more attractive than the diesel swap I was thinking about. I am already combing the local classifieds for a rolled up GM donor vehicle. 
shopping list so far:
LL8
4l60
LL8 PCM
LL8 wiring harness
Throttle pedal and switch
Marks GM/Toyota adapter
GM fuel pump and sender
custom engine mounts
custom oil pan
custom exhaust
GM gearshift lever
custom fan shroud
custom coolant hoses
what other specific items have i forgotten?
very nice build btw. very interested in this as a kit.
LL8
4l60
LL8 PCM
LL8 wiring harness
Throttle pedal and switch
Marks GM/Toyota adapter
GM fuel pump and sender
custom engine mounts
custom oil pan
custom exhaust
GM gearshift lever
custom fan shroud
custom coolant hoses
what other specific items have i forgotten?
very nice build btw. very interested in this as a kit.
- Thread starter
- #146
Efidiy, any idea what those pans will go for? TwoTonic, how about your t-case adapter? Personally since part of the swap goal would be to increase mileage a split case and set of lock-out hubs would be a nice way to go. Whichever route you go this is a very interesting swap, much more attractive than the diesel swap I was thinking about. I am already combing the local classifieds for a rolled up GM donor vehicle.
We haven't done a split-case yet but are thinking the combination you describe would be good for mileage in combination with the lock-out hub conversion.
are you thinking of a split case from an FJ6x?
alia176
SILVER Star
I'm curious if the build is finished and whether or not the vehicle is operational. Are there any pics of this particular conversion?
Cheers.
Cheers.
- Thread starter
- #148
Hi! Yep, that's a pretty good start on the list. Other 'small' items include a chunk of the BCM harness (although you don't need the BCM itself), sensors pulled from your old motor for gauge compatibility, 4L60 shift cable...
Also, the GM PCM will need a light 'tune'-- mainly turning OFF VATS and stuff that's not present-- so access to HP Tuners is advised.
Steering tends to get unacceptably light when you convert AWD to part time - if the point of an engine conversion is road use, then a part time conversion is probably not a major design goal.
Said another way, if I am designing around a part time system geared towards offroad use, the 1ZFE engine is already a perfect platform. Probably the single biggest concern I would have around a 4.2 swap is the effectiveness of engine braking in hardcore offroad use vs. the 1ZFE, which for all of its narrow power band holds a steep descent pretty close to a manual transmission when you have low diff gears (5.29).
Most of my miles are onroad, but I value descent engine braking very highly from rock crawling to steep passes in winter conditions.
Food for thought?
The 80 is my first AWD vehicle. Wasn't sure what to think of that at first, but I've since decided it's a major plus. A big, heavy vehicle is a safer one with AWD for most consumers.
Don't get me wrong, I can understand all the reasons people want locking hubs and the project that goes with it. That's where I was in the past.
Of course, then it was with a manual transmission. I'm still not sure what to think about the auto, haven't really got it out on trails that I know well would be a fair test of that.
Personally, I would prefer keeping the 80's T-case, with it's track record of reliability. But really it's whatever is going to offer comparable rugged performance in drive train components without getting into something exotic that is going to provide the consumer the most value.
If it's possible to provide alternative configurations, that's cool, but most people are looking for a decidedly painless approach when it comes to swaps. This one is headed that way if all the pieces continue to fall into place.
Don't get me wrong, I can understand all the reasons people want locking hubs and the project that goes with it. That's where I was in the past.
Of course, then it was with a manual transmission. I'm still not sure what to think about the auto, haven't really got it out on trails that I know well would be a fair test of that.
Personally, I would prefer keeping the 80's T-case, with it's track record of reliability. But really it's whatever is going to offer comparable rugged performance in drive train components without getting into something exotic that is going to provide the consumer the most value.
If it's possible to provide alternative configurations, that's cool, but most people are looking for a decidedly painless approach when it comes to swaps. This one is headed that way if all the pieces continue to fall into place.
I assume we should add these to the list?:
- custom power steering hose/fittings
- custom AC hoses/fittings
- Cruise control items?
Will a lift kit be needed?
Also, some custom wiring will be needed to mate the engine harness into the dash gauges.
TT
Forgive me if you have been asked/answered on this. In looking at pics of the 4.2 it appears the power steering and A/C compressor are on the opposite side of the 1 FZ and where we need them. Are there applications where this is not the case and can other GM factory brackets be used, or did you fab up brackets to relocate them or did you just route long hoses to the opposite sides?
Thanks
Forgive me if you have been asked/answered on this. In looking at pics of the 4.2 it appears the power steering and A/C compressor are on the opposite side of the 1 FZ and where we need them. Are there applications where this is not the case and can other GM factory brackets be used, or did you fab up brackets to relocate them or did you just route long hoses to the opposite sides?
Thanks
My nephew had the #6 cylinder go bad on his 97 LX450
So this build really intrest us now. is it progressing and if so is it working like expected?
So this build really intrest us now. is it progressing and if so is it working like expected?
So how is the progress? Any updates?
wow, great thread, this is something i have to look into in the near future, pictures look great and the the engine bay looks a lot less cluttered
TwoTonic - I have to compliment you both on your ingenuity and boldness, and also on your keeping us updated on the progress of the conversion.
My '96 LX450 has only 143K miles and is running without major issues, but I would jump ALL over a comprehensive DIY LL8 kit either with or without the engine and tranny included.
After 10 years of ownership, I have this truck just where I like it other than the @#$%^& asthmatic engine. I have been toying with the idea of a TRD supercharger, but have shied away due to the inherent deficiencies of the engine and the higher stress the forced induction places on everything.
I have hesitated about a small block V8 swap due to the fitting complications.
I would put _many_ more miles on my truck if it were smooth, quiet and powerful. I don't care about absolute maximum thrust, just a refined capable feeling. Right now I dread the steep passes and near-vertical back roads of Idaho, and won't even consider a trip to the 11,000 foot passes of the Colorado High Country. Last summer my wife and I did a two week tour of central Colorado (for a week we never dropped below 8,000 feet).... and we took her RAV4 V6 instead of the Lexus because we couldn't stand the idea of the 2500 miles of stressful highway driving in The Pig, and the associated fuel expense. I am sure the LL8 conversion would make trips like this practical and pleasant.
The fuel savings are a welcome bonus, but they aren't the major factor for me.
A couple of specific questions:
Will you offer turn-key conversions at your shop? My truck is a DD and downtime is a major concern. I could easily handle a week while you guys did everything and tweaked the computer. Could you provide a ballpark SWAG price? I can be there in eight hours
If not, I would attempt the conversion in my garage (I am an ex-A&P mechanic) but the critical welding (engine mounts) and other fabrication stuff has me a little worried, and I hate to traipse all over town getting custom bits like hoses made up.
Cruise control - how is it accomplished? The OEM cruise control actuator is troublesome and impractical to replace ($$$) if it fails completely. Is cruise functionality done through the LL8 ECM?
BTW, can someone post a dyno chart of a stock US-spec FZJ80?
Thanks.
John Davies
Spokane WA
My '96 LX450 has only 143K miles and is running without major issues, but I would jump ALL over a comprehensive DIY LL8 kit either with or without the engine and tranny included.
After 10 years of ownership, I have this truck just where I like it other than the @#$%^& asthmatic engine. I have been toying with the idea of a TRD supercharger, but have shied away due to the inherent deficiencies of the engine and the higher stress the forced induction places on everything.
I have hesitated about a small block V8 swap due to the fitting complications.
I would put _many_ more miles on my truck if it were smooth, quiet and powerful. I don't care about absolute maximum thrust, just a refined capable feeling. Right now I dread the steep passes and near-vertical back roads of Idaho, and won't even consider a trip to the 11,000 foot passes of the Colorado High Country. Last summer my wife and I did a two week tour of central Colorado (for a week we never dropped below 8,000 feet).... and we took her RAV4 V6 instead of the Lexus because we couldn't stand the idea of the 2500 miles of stressful highway driving in The Pig, and the associated fuel expense. I am sure the LL8 conversion would make trips like this practical and pleasant.
The fuel savings are a welcome bonus, but they aren't the major factor for me.
A couple of specific questions:
Will you offer turn-key conversions at your shop? My truck is a DD and downtime is a major concern. I could easily handle a week while you guys did everything and tweaked the computer. Could you provide a ballpark SWAG price? I can be there in eight hours
If not, I would attempt the conversion in my garage (I am an ex-A&P mechanic) but the critical welding (engine mounts) and other fabrication stuff has me a little worried, and I hate to traipse all over town getting custom bits like hoses made up.Cruise control - how is it accomplished? The OEM cruise control actuator is troublesome and impractical to replace ($$$) if it fails completely. Is cruise functionality done through the LL8 ECM?
BTW, can someone post a dyno chart of a stock US-spec FZJ80?
Thanks.
John Davies
Spokane WA
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